The invention herein relates to exhaust pipe joints and clamps therefor, the principal purpose of the invention being to provide a joint and clamp which will reduce if not eliminate emission from exhaust system joints.
The basic principles of the invention and the general background therefor will be found in U.S. Pat. No. 3,788,677. The invention herein is intended as an improvement and/or variation of the invention disclosed in said patent. The improvement relates to the convenience of handling the clamp of the prior patent by virtue of certain structural changes made thereto. The variation relates to a slightly different form of end bead formed on one of the exhaust pipes.
With respect to handling of the clamp, in the use thereof the prior disclosure showed the forming of the clamp in two pieces or halves. There was a rectangular bight formed on the first end of one half and a simple flat tongue formed on the first end of the other half, the tongue lying in the bight and being centered and held against movement because the two halves were held in axial alignment on the joint. The concave grooves of the halves engaged the abutted beads and could not move laterally of one another. Although this is efficient and economical, the workman being required to assemble the clamp onto a joint has to handle two separate members. The invention herein contemplates an articulated connection which is as efficient but in which the two halves are preferably permanently coupled to one another as a part of the manufacturing process so that the workman in assembling the joint need not handle two separate pieces.
In addition to solving the problem of handling two halves of the clamp, the use of a bolt and nut for fastening the second ends together posed requirements again of handling a pair of members (bolt and nut) in addition to manipulating the two halves of the body of the clamp. Also in tightening the bolt and nut, one has to be twisted and the other held. The invention herein contemplates permanently securing the nut to the second end of one half so that all the workman need do is to thread the bolt into the nut and tighten the bolt.
With respect to different forms of the beads on the ends of the pipes, the clamp of the patent as well as that herein is of a construction which will permit the application of an axial force of one pipe against the other to tighten their engagement if one end is provided with a round bead and the other end is provided with a flared bead--sort of a male and female connection. This form of joint is capable of being maintained substantially emission-free even if the pipes are not perfectly aligned, and one of the forms of the invention herein proposes a clamp structure which allows for substantial misalignment.
The clamp features of the invention herein are applicable to structures not necessarily consisting of pipe joints and the invention is considered broad enough to cover clamps per se using such features.
With respect to prior art known by the applicants, that which is of record in the patent referred to is believed typical.